McIntosh XR27 User Manual

XR27 Loudspeaker System

Owner’s Manual

XR27

McIntosh Laboratory, Inc. 2 Chambers Street Binghamton, New York 13903-2699 Phone: [phone] FAX: [phone]

WARNING - TO REDUCE RISK OF

FIRE OR ELECTRICAL SHOCK, DO

NOT EXPOSE THIS EQUIPMENT TO

RAIN OR MOISTURE.

IMPORTANT SAFETY

INSTRUCTIONS!

PLEASE READ THEM BEFORE

OPERATING THIS EQUIPMENT.

NO USER-SERVICEABLE PARTS

INSIDE. REFER SERVICING TO

QUALIFIED PERSONNEL.

General:

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Warning: To reduce risk of fire or electrical shock,
do not expose this equipment to rain or moisture.
This unit is capable of producing high sound pres­sure levels. Continued exposure to high sound pres­sure levels can cause permanent hearing impair­ment or loss. User caution is advised and ear pro­tection is recommended when playing at high vol­umes.

6. Only use attachments/accessories specified by the
manufacturer.

Installation:

7. Install in accordance with the manufacturer’s instruc­tions.

8. Do not install near any heat sources such as radiators,
heat registers, stoves, or other equipment (including
amplifiers) that produce heat.

9. Do not use this equipment near water.

10. Do not expose this equipment to dripping or splashing
and ensure that no objects filled with liquids, such as
vases, are placed on the equipment.

11. Use only with the cart, stand, tripod,
bracket, or table specified by the manufac­turer, or sold with the equipment. When a
cart is used, use caution when moving the
cart/equipment combination to avoid in­jury from tip-over.

Care of Equipment:

12. Clean only with a dry cloth.

13. Do not permit objects or liquids of any kind to be
pushed, spilled and/or fall into the equipment through
enclosure openings.

Repair of Equipment:

14. Refer all servicing to qualified service personnel. Ser­vicing is required when the equipment has been dam­aged in any way, liquid has been spilled or objects have
fallen into the equipment, the equipment has been ex­posed to rain or moisture, does not operate normally, or
has been dropped.

15. Do not attempt to service beyond that described in the
operating instructions. All other service should be re­ferred to qualified service personnel.

16. When replacement parts are required, be sure the ser­vice technician has used replacement parts specified by
McIntosh or have the same characteristics as the origi­nal part. Unauthorized substitutions may result in fire,
electric shock, or other hazards.

17. Upon completion of any service or repairs to this prod­uct, ask the service technician to perform safety checks
to determine that the product is in proper operating
condition.

2

Thank You

Table of Contents

Your decision to own this McIntosh XR27 Loudspeaker
System ranks you at the very top among discriminating
music listeners. You now have “The Best.” The McIntosh
dedication to “Quality,” is assurance that you will receive
many years of musical enjoyment from this unit.

Please take a short time to read the information in this
manual. We want you to be as familiar as possible with all
the features and functions of your new McIntosh.

Please Take A Moment

The serial number, purchase date and McIntosh Dealer
name are important to you for possible insurance claim or
future service. The spaces below have been provided for
you to record that information:

Serial Number:

Purchase Date:

Dealer Name:

Technical Assistance

If at any time you have questions about your McIntosh
product, contact your McIntosh Dealer who is familiar
with your McIntosh equipment and any other brands that
may be part of your system. If you or your Dealer wish ad­ditional help concerning a suspected problem, you can re­ceive technical assistance for all McIntosh products at:

McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, New York 13903
Phone: [phone]
Fax: [phone]

Customer Service

If it is determined that your McIntosh product is in need of
repair, you can return it to your Dealer. You can also return
it to the McIntosh Laboratory Service Department. For as­sistance on factory repair return procedure, contact the
McIntosh Service Department at:

McIntosh Laboratory, Inc.
2 Chambers Street
Binghamton, New York 13903
Phone: [phone]
Fax: [phone]

Copyright 2003  by McIntosh Laboratory, Inc.

Safety Instructions ............................................................. 2

Thank You and Please Take a Moment ............................. 3

Technical Assistance and Customer Service ..................... 3

Table of Contents and Important Information ................... 3

Introduction ....................................................................... 4

Performance Features ........................................................ 5

Dimensions ........................................................................ 6

Installation ....................................................................... 10

How to Connect using a single amplifier ........................ 12

How to Connect using two amplifiers............................. 14

How to Connect using three amplifiers........................... 16

Specifications .................................................................. 18

Packing Instruction .......................................................... 19

Important Information

Caution: The XR27 weight is 84 pounds (38kg) and requires

two or more persons to safely handle.

1. Loudspeaker Cables of adequate size are important to ensure
that there will be no significant power loss or heating. Cable
size is specified in Gauge numbers or AWG (American Wire
Gauge). The smaller the Gauge number, the larger the wire
size:

If the Loudspeaker Cables are 25 feet (7.62m) or less, use at
least 18 Gauge (AWG) wire size or larger.
If the Loudspeaker Cables are 50 feet (38.1m) or less, use at
least 14 Gauge (AWG) wire size or larger.
If the Loudspeaker Cables are 100 feet (76.2m) or less, use at
least 12 Gauge (AWG) wire size or larger.
The Loudspeaker Connection Terminals can accept up to 12
Gauge (AWG) wire.

2. For additional connection information, refer to the owner’s
manual(s) for any component(s) connected to the XR27
Loudspeaker System.

3. The XR27 has built-in speaker protection in the form of four
automatic resetting solid-state devices as part of the
crossover networks. One protects the tweeters, one for the
midranges and two for the woofers. The characteristics of this
protection are that a certain amount of overdrive is allowed
but extended periods of overdrive will trigger protection. If an
obvious lack of high, mid or low frequencies is noticed, the
Loudspeaker Protection Device may have activated. The
protection devices will automatically reset when the volume
control is reduced significantly and kept low until the output
of the affected Loudspeaker Element returns to normal.

4. When the XR27 Loudspeaker System is driven by more than
one amplifier, the output levels of the different amplifiers
connected to the Loudspeaker System must be adjusted to
achieve a proper balance between the low, midrange and high
frequencies reproduced. This adjustment is best achieved
through the use of audio test equipment operated by a
qualified installer.

5. The XR27 is designed to be used with a Subwoofer, like a
McIntosh PS112, in order to hear the entire audible range of
sound.

3

Introduction

McIntosh Acoustic Engineers have refined the Loud­speaker System concept to provide superior sound quality
in a versatile enclosure with five different installation
methods.

The Low Frequency Section of the System consists of
four 8 inch Woofers. They have a large magnet assembly
and long cone excursions with very low levels of harmonic
distortion and frequency response down to 80Hz. Refer to
figure 1. The Woofer also incorporates McIntosh’s Pat-

The 6-1/2 inch Midrange Driver also incorporates

McIntosh’s Patented LD/HP

1

Magnetic Circuit Design with
shielding to greatly reduce any external magnetic field.
Refer to figures 1, 2 and 3. The low distortion of this
Midrange Driver results in the incredible smoothness and
clarity in the reproduction of the human voice. The five 1
inch soft dome Tweeters are inline and connected to pro­duce a Bessel Function Array. Refer to figure 4. The indi-

Figure 1

ented LD/HP

1

Magnetic Circuit Design with shielding to
greatly reduce any external magnetic field. Extensive in­vestigating and testing re­sulted in a new design con­cept which utilizes a pair of
aluminum shorting sleeves

LD/HP

Conventional

in the magnetic circuit. Re­fer to figure 2. The sleeves
virtually eliminate the nega­tive influence of the fluctu­ating voice coil field on the
permanent magnet field.
This results in lower distor-

Figure 2

tion due to more linear magnetic flux in the voice coil gap.
Refer to figure 3. Additional benefits are less volume com­pression due to
improved heat
transfer through
the sleeves and a
cooler operating
voice coil. Both
measurements, as
well as critical
listening, reveal
ten times less dis­tortion than previ-

Figure 3

ous designs.

Figure 4

vidual tweeter amplitudes and phase relationships are ad­justed so the array acts as a high frequency point source.
One advantage of such an arrangement is a very smooth
and even acoustic polar response. This allows the listener
to move off axis without suffering a change in high fre­quency output. The use of multiple tweeters, combined
with a heat sink, also provides greatly increased power
handling at high frequencies.

The Crossover Networks used in the XR27 Loud­speaker System are designed to ensure an even frequency
response over the entire audible range. The Low Fre­quency Crossover Network is a Third Order design utiliz­ing Capacitors and Inductors with high current capacity.
Refer to figure 5. Low Loss (DCR) Inductors in the Low

Figure 5

1

LD/HP Pat. No. 5,151,943

4

Frequency Network, are chosen not to exhibit any core
saturation even at high power levels. This prevents the ad-

dition of distortion to the music at low frequencies. The
Midrange and High Frequency Crossover Networks utilize
both Second and Third Order Crossover Designs. The Ca­pacitors and Inductors used are of a high current capacity
design and include low loss (ESR) Polypropylene and
Mylar types. The Crossover Networks utilize self resetting
high current Poly-Switches to provide an extra measure of
protection.

The enclosure is an important part of the XR27 Loud­speaker System and consists of a massive extruded alumi­num enclosure. Refer to figure 6. The front mounting
board is
made of
3/4 inch
thick
MDF that
houses
the four 8
inch
Woofers,
one 6-1/2 inch Midrange and the five one inch inline
Tweeter Drivers. Refer to figure 7. It has multiple front to

Figure 6

Introduction and Performance Features

Performance Features

Patented LD/HP Technology

•

The McIntosh Low Frequency and Midrange Loudspeaker
Elements feature the patented LD/HP Magnetic Circuit
Design. This design, when compared to conventional
Loudspeaker Elements, reduces distortion significantly. It
also increases power handling and efficiency.

Neodymium-Iron-Boron Alloy Magnets

•

The five one inch Dome Tweeters use Neodymium-Iron­Boron Alloy that has a high flux density per unit of volume
and helps to keep the weight to a minimum.

Bessel Function Array

•

The individual tweeter amplitudes and phase relationships
of the five tweeter array are adjusted to act as a high
frequency point source

Shielded Magnetic Field

•

The XR27 may be used in Home Theater Installations near
a television receiver or monitor without causing the
television image to degrade. McIntosh has designed
special shielding around the magnetic structure of the
XR27 Loudspeaker Elements to prevent interference.

Figure 7

back internal braces to form a dampened rigid Structure.
The XR27’s small footprint allows for a variety of differ­ent placements in a room.

High Power Handling

•

The Loudspeaker Elements and Crossover Components of
the XR27 are all chosen for use with powerful amplifiers
up to 1,200 watts.

Versatile Operation and Placement

•

In additional to the regular connections, the XR27 Loud­speaker System provides separate connections for Bi-Am­plification hookups. The Crossover Network has provi­sions to ensure the best performance when the Loud­speaker System is mounted in a wall.

Gold Plated Input Connectors

•

The XR27 input connectors are gold plated for superior
corrosion resistance and high electrical conductivity.

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